I now realize how tough it would be to create a 'tripod ring'. With the Hartbeli setup, you will only be able to get landscape shifting or you can rotate the camera and L/R shift a portrait mode picture to make it a little wider when you join the two or three photos together.

http://www.photoscala.de/Artikel/Neue-Adapter-von-ZoerkThis one won't prevent you from using the tilt, however, the camera sensor plane won't be level anymore. And you won't be able to take a picture of the US Capitol building lets say with some tilt, and then shift it right and left to make a panorama. (*Now that I think about it some more, you would have to point the camera up, lock the tripod, then tilt to make your camera level, so it should work)